Device and method for the plugging of services in conduits

ABSTRACT

A plug for a tubular service entrance of a conduit, wherein the plug includes a core body having a central hollow channel extending from a first end to second end of the core body; at least one flexible fin extending radially outwardly from the core body and having an outer diameter greater than the inner diameter of the tubular service entrance so that the plug is adapted to fit tightly into the tubular service entrance, and wherein the at least one flexible fin is deformable to adapt to the shape of the service entrance and apply a lateral force against the inner diameter of the service entrance. A plug dispensing magazine for storing and dispensing service entrance plugs to be service entrances of a conduit prior to installation of a liner in the conduit and a method of sealing the service entrances.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation under 35 U.S.C. §120 of U.S.application Ser. No. 12/544,320 filed on Aug. 20, 2009, the entiredisclosure of which is hereby incorporated by reference herein, whichclaims the benefit under 35 U.S.C. §119(e) of the earlier filing date ofU.S. Provisional Application Ser. No. 61/090,606 filed on Aug. 20, 2008,the entire disclosure of which is also hereby incorporated by referenceherein.

FIELD OF INVENTION

The invention relates to the rehabilitation of underground smalldiameter potable water distribution conduits as well as large diameterwatermains.

BACKGROUND OF THE INVENTION

Trenchless methods are known for the rehabilitation of sewer and potablewater conduits. Known methods include cured-in-place-piping (CIPP) andpulled-in-place-piping (PIPP), the major difference between the twoapplications being internal pressure. CIPP is achieved by producing acomposite tube that is inserted or inverted into a host pipe. Thecomposite is cured inside the host pipe to activate a resin system toproduce a solid composite lining inside the pipe. An example of CIPP isdisclosed in U.S. Pat. No. 5,384,086, this disclosure of which isincorporated by reference herein. Another method is disclosed inCanadian Patent #2 361 960 (US 2002/0058121) entitled “A Tubular Linerand Method of Rehabilitating of Conduits”, this disclosure of which isincorporated by reference herein. There is, however, a need for improvedinstallation devices and methods to increase product quality,installation reliability, and execution efficiency.

SUMMARY OF THE INVENTION

An embodiment of the invention provides improved installation devicesand methods related to the lining of the inner surface of an undergroundpotable water conduit. In accordance with an embodiment of theinvention, a non-protruding, polymeric finned plug which is insertedinto a protruding, partially protruding, non-protruding, or even in asaddle service. The plug is inserted entirely within the service or holeleaving the face of the service or hole available and withoutinterference to the liner and its polymeric resin so as a leak-tightbond may be formed. The absence of any plug lip or shoulder assures thatno foreign matter remains entrapped between the liner/polymeric resincombination and the service or inner wall of the host pipe. Thisminimizes the possibility of entrapped air around the service face andhost pipe which could lead to liner delamination after the service isopened and the water pressure is re-established in the water conduit.This aspect is directed specifically to product quality.

An embodiment of the invention also covers an improved leak-tightness ofthe service plugging operation. When the polymeric flexible multileveledfinned plug is inserted into a service, the oversized fins flex anddeform to conform to and apply a constant external force against thelateral inner wall of the service or hole creating a leak-tight seal ofthe service. The multiple levels of fins add additional layers ofleak-tight protection.

An embodiment of the invention also addresses the loading and dispensingof the above described polymeric finned plugs. Where long conduits withnumerous services entrances are involved, which is often the case onresidential and commercial streets, the total time required to plug allservices within the entire conduit is comprised of the time to load theplugging device and plug each service plus the time required to move theplugging equipment into position for each service. If the pluggingequipment needs to be pulled out of the conduit to load a plug onto theplugging device, this lengthens the total time required to completeplugging of all services in a conduit. The invention addressespre-loading a large quantity of plugs onto a magazine which is mountedon the plugging device. By pre-loading numerous plugs into the magazineand introducing the plugging equipment and loaded plug magazine avoidsthe need to pull the plugging device out of the conduit to load a plugonto the plugging device between each service plugging operation. Themounted magazine and dispensing mechanism must be sufficiently small tofit into conduits of small diameter as is often the case in potablewater distribution conduits.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an elevational view of a polymeric flexible finned plug usedto render service entrances leak-tight against polymeric resin from theliner according to an embodiment of the invention. FIG. 1B is a planview of the plug of FIG. 1A.

FIG. 2A is a plan view a plug magazine according to an embodiment of theinvention with high plug loading capacity with spring-loaded pusherforcing the plugs to advance through the magazine as they are strippedaway individually for use. FIG. 2B is an elevational view of the plugmagazine of FIG. 1A.

FIG. 3 is a plan view of the plug magazine plug dispensing systemaccording to an embodiment of the invention showing the spring-loadedretaining fingers used to hold back the series of plugs in the magazine.

FIG. 4 is an elevational view of a conforming material dispensing systemassembly according to an embodiment of the invention.

FIG. 5 is an enlarged view of the conforming/sealing material pneumatic,remote actuated dispenser according to an embodiment of the inventionincluding the single or multi-part sealing material.

FIG. 6 is an enlarged elevational view of the compact, right-angleconforming/sealing material dispensing valve according to an embodimentof the invention including a multi-element static mixing nozzle used tomix multi-part material.

FIG. 7 is an enlarged elevational view of the compact, right-angleconforming/sealing material dispensing valve according to an embodimentof the invention depicting the compact size and appropriate angularconfiguration between the inlet of the dispensing valve and the outletof the conforming/sealing material through the static mixing nozzlenested within the plug insertion tool and capable of injecting thematerial once the plug is installed in the service without having tochange equipment or position.

FIG. 8 shows an assembled view of the polymeric flexible-finned plugpositioned within an irregular shaped hole whereby the service isinstalled in a saddle on the outer face of the pipe.

FIG. 9 shows an elevational view depicting a plug dispensing magazineaccording to an embodiment of the invention mounted on commerciallyavailable robot.

FIG. 10 an end view of an embodiment of the invention having mountingmultiple plug dispensing magazines onto a commercially available robot.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1A and 1B refer to an embodiment of the invention which is a plug1 made of polymeric material such as polyethylene, polypropylene,polyurethane, polyamide, and synthetic rubbers or other polymeric orrubberized material which is relatively rigid and approved by arecognized authority for use in potable water application. Plug 1 isinserted in a pipe service entrance prior to lining the pipe in order tokeep uncured resin from the lining process from infiltrating and thusclogging the service entrance. The plug 1 has a core body 3 and at leastone thin flexible fin 2 extending therefrom. The core body 3 may containradial vent holes 4 and the at least one thin flexible fin 2 may containlongitudinal vent holes 21 for a function to be described in a laterembodiment. The fins 2 are of a diameter slightly larger than thenominal diameter of the service entrance at its time of installation.Since the fins 2 are flexible and have memory, during the insertion ofthe plug 1 into the service entrance, the fins 2 flex and deform as theplug 1 is inserted into the service, however, the fins' 2 materialmemory will want to return to their original configuration except forsome plastic deformation. The oversized flexible fins 2 will apply aconstant lateral force against the inner wall of the service entrancethus allowing for sealing the service entrance. In the illustratedembodiment, in order to increase certainty and reliability that theservice entrance is leak-tight, fins 2 are multi-layered with at leasttwo layers of fins 2 longitudinally spaced about core 3. With each fin 2being flexible and at various heights within the service, variousservice diameters and surface conditions are accommodated sealed at eachfin 2. This provides for extra levels of leak-tightness within a compactplug design.

The plug 1 configuration and its features as described in embodiments ofthe invention will accommodate variations in service entrance diameterand surface finish found at the time of conduit rehabilitation, whichcan vary greatly from case to case due to reasons such as age, qualityof valve construction, quantity and quality of water having passedthrough the service entrance over its time of use since entry intoservice, and other such factors. The described features of theoversized, flexible, multi-leveled fins 2 shall serve to maximize thenumber of cases whereby one plug design will satisfy the largestpossible service entrance configurations of a given nominal diameter.

The plug 1, which is inserted into the service entrance prior to conduitlining, allows the face of the service entrance be clear of anyobstructions so that the polymeric resin and liner may form a clean,strong, and homogeneous bond with the face of the service entrance orinner wall of the conduit in the case where the service entrance is notpenetrating beyond the inner wall of the conduit.

Embodiments of the invention apply not only to services which areprotruding through an inner face of a conduit but also to services whichare either; a) tapped into a conduit but the face of the plug is even orwithin the inner wall of the conduit, or b) the service is supported bya saddle or conduit joining union whose inner diameter is nominallyequal to the outside diameter of the host pipe(s). In this case, a holeis present in the host pipe approximately in-line with the axis of theservice entrance being supported by the saddle or union.

This plug 1 design allows for it to be inserted entirely within theservice and thus not protruding the service within the conduit. Theadded advantage of this as opposed to a plug design which protrudeswithin the conduit is that when the liner is installed in a subsequentoperation, the liner and its resin have virtually no opportunity to haveair bubbles or pockets entrapped at the interface between the liner andthe plug 1.

FIGS. 2A and 2B refer to another aspect of the invention which is thehigh loading capacity and distribution magazine 5 for the abovedescribed flexible finned polymeric plugs 1. Water mains to berehabilitated are typically long and the preparation work to beperformed prior to lining, notably the service plugging operation, mustbe accomplished from within the conduit. Embodiments of the inventionreduce operation time, increase efficiency by minimizing the number oftimes that the equipment sent into the conduit be pulled out to loadwith plugs. Embodiments of the invention include a preloaded plugdistribution magazine 5 with a large number of plugs 1, ideally enoughto cover the number of service entrances in the conduit is required andis the basis for the invention.

Referring to FIG. 2, it is shown that a long, spring-loaded magazine 5or track capable of being loaded with several plugs 1. The plugdispensing magazine 5 is designed to be able to be retrofitted directlyonto commercially available equipment 6 (FIGS. 4 and 9) specific forconduit rehabilitation. Examples of commercially available equipmentsuch as remotely controlled robots are disclosed in U.S. Pat. Nos.4,648,454; 5,318,395 and 5,368,423, the disclosures of which areincorporated by reference herein. In order for the plug insertionequipment to work properly, the force required to advance a plug 1 intoposition after one has been removed by the plug insertion tool 7 (FIG.7) should be constant. In the invention, this is assured by a constantforce biasing member or spring 23 activating a plug pusher 9. As well asapplying a constant force, the utilized spring has a very long stroke.This allows for a magazine 5 to be quite long and having a loadingcapacity of many plugs 1.

The cross sectional profile of the magazine 5 or track is shaped in sucha manner as to support the plugs 1 in between two levels of fins 2. Thisassures that the plug 1 are always presented to the plug strip-off pointat the same level.

At the front end of the magazine 5 is a set of spring-loaded plugretaining fingers 8 (FIG. 3) which have a higher spring force than theplug advancement force. This keeps the plugs from being pushed through.The spring-loaded retaining finger(s) 8 can be singular or dual. Theyare made from a flexible material such as spring steel, and angled tohold back the plugs 1 in the magazine 5. The plug insertion toolapproaches the plug 1 in position ready to be stripped off fromunderneath the plug 1. The plug insertion tool engages the waiting plug1 and then moves forward, thereby forcing the retaining fingers 8 tospread open and allow the plug 1 to be stripped from the magazine 5.Concurrently, the constant force plug advancing pusher 9 moves the nextplug 1 into position ready for the next cycle. The pusher 9 acts on thetrailing plug 10 of the series and thus the entire series of plugs 1advances.

Referring again to FIG. 9, it can be seen that due to the plugdispensing magazine's low profile, it can be mounted directly onto acommercially available robot 6 used for rehabilitating small diameterconduits and still fit.

FIG. 10 refers to the possibility of mounting multiple plug dispensingmagazines 5 onto a commercially available robot 6. By offsetting theplug dispensing magazines 5 a, 5 b angularly, it is possible to mountmore than one magazine on the robot 6. This allows for the possibilityof either multiplying the total number of plugs 1 which can bepre-loaded prior to sending the equipment into the conduit or for havingmore than one size of plugs such that once the equipment inside theconduit, the operator, who is operating the equipment remotely, can plugservice of various sizes without the need to withdraw the equipment fromthe conduit to change the size of plugs in the magazine 5. Again thepurpose of this is to minimize the time required to plug the servicesand thus increasing operation efficiency.

Yet another aspect of the invention is directed at plugging serviceentrances against resin infiltration during the lining process whenservice entrances are irregular in shape to the point whereby a usualplug 1 cannot guarantee leak-tightness. FIG. 4 shows aconforming/sealing material dispensing system 11 comprising laterdescribed elements 12, 13, 14 and 15 mounted on commercially availableequipment 6 designed and built for rehabilitation of small diameterpotable water conduits. With rigid, semi-rigid, or even multi-levelflexible-finned plugs 1 as described earlier, there exists cases where aservice entrance, either a service tapped directly into the host pipe ora service entrance made up of a valve in a saddle, is of a shape and/orsurface finish which is not round enough or smooth enough in finishallowing for a leak-tight seal by the plug 1. In these suchcircumstances, the invention provides for injecting a material whichlends itself to injection, fills gaps between the plug 1 and the serviceentrance wall, approved for contact with potable water, and cures to ahardness allowing for it to be drilled out after the lining processalong with the plug itself.

Embodiments of the invention include a pneumatic remote operatedinjection device 12, a cartridge of single or multi-partconforming/sealing material 13 (FIG. 5), a single or plurality offlexible hoses 14 for delivering the conforming/sealing material 13, aremote operated dispensing valve 15 to control the moment at which theconforming/sealing material 13 is required, a static mixer 16 requiredfor mixing multi-part conforming/sealing material. The sum of the abovestated components is mounted on a commercially available robot 6designed for performing plugging, drilling and inspection within smalldiameter potable water conduits and the like. The dispensing valve 15(FIG. 6) is designed and constructed to be able to fit within smalldiameter potable water conduits. It is pneumatically operated and can beactuated remotely. Its inlet and outlet are angled at 90 degrees for acompact arrangement. A nozzle 17 with if necessary a static mixer 16 isfixed onto the dispensing valve 15. The static mixer 16 is required inthe case where multi-part conforming/sealing materials are used. FIG. 7shows the dispensing valve 15 mounted onto the plug insertion toolsupport block 18 along with the plug insertion tool 7 and a plug 1 whichwould previously have been stripped from the plug dispensing magazine 5.The conforming/sealing single or multi-part material arriving from thedispenser arrives under pressure via flexible tubes (not shown). At theoperator's discretion, the dispensing valve 15 is opened and the singleor multi-part conforming/sealing material flows through the dispensingvalve 15 and through the nozzle 17 which is equipped with or without astatic mixing element 16 required for multi-part sealing materials. Thenozzle 17 passes through an opening within the plug insertion toolsupport block 18 and plug insertion tool 7. If the service entrance wasdeemed to be of irregular shape or of unsmooth finish prior to theinsertion of the plug 1, once the plug 1 is inserted into the serviceentrance, the operator triggers a dosed shot of conforming/sealingmaterial. The conforming/sealing material passes through the centralchannel of the plug 1 (FIG. 8) then out through radial vent holes 4 inthe plug 1 to fill the gaps between the flexible multilevel fins 2, theinner wall 20 of the service or hole and the outer core of the plug.Longitudinal vent holes 21 through the lower fins 2 allow for air whichwas trapped between the fins 2 to escape so the conforming/sealingmaterial can fill all the voids and conform to the inner wall 20 of theservice entrance regardless of its shape and/or surface finish andadhere to all the walls and seal the service entrance rendering itleak-tight. Longitudinal vent holes 21 in the lowest flexible fin 2allow for some of the conforming/sealing material to escape providingthe operator with evidence, via the camera 22, that theconforming/sealing material has been injected in sufficient quantity.Should there not have been enough conforming/sealing material injectedto fill the gaps and ooze through the longitudinal vent holes 21 of thelowest flexible fin 2, then the operator can trigger a supplemental shotof material. This is repeated until the operator sees the material oozeout the lowest fin 2. In order to contain the conforming/sealingmaterial and from keeping it from infiltrating into the inner side ofthe service entrance, the topmost, or leading flexible fin 2 along withthe top portion of the plug 1 are continuous without longitudinal ventholes 21 or openings. This also allows for a front line defense againstleaks or at the very least keeps the possible path for resininfiltration to a minimum, thus reducing the size of the possible pathsfor the resin to travel.

If not otherwise stated herein, it may be assumed that all componentsand/or processes described heretofore may, if appropriate, be consideredto be interchangeable with similar components and/or processes disclosedelsewhere in the specification, unless an express indication is made tothe contrary.

If not otherwise stated herein, any and all patents, patentpublications, articles and other printed publications discussed ormentioned herein are hereby incorporated by reference as if set forth intheir entirety herein.

It should be appreciated that the apparatus and methods of the inventionmay be configured and conducted as appropriate for any context at hand.The embodiments described above are to be considered in all respectsonly as illustrative and not restrictive.

1. An apparatus for plugging a plurality of service entrances in aconduit prior to installation of a liner in the conduit, the apparatuscomprising: a remotely controlled robot; at least one plug dispensingmagazine mounted on the robot for storing and dispensing a plurality ofservice entrance plugs; each plug having a core body having a centralhollow channel, at least two longitudinally spaced apart flexible finsextending radially outwardly from the core body and a plurality ofradial vent holes located in between the longitudinally spaced apartflexible fins; each magazine supporting the plugs at a constant heightand comprising: at least one spring-loaded retaining finger forretaining the plugs at a plug strip-off end of each magazine; a plugpusher for advancing the plugs along the magazine; and a biasing memberfor applying a constant force against the plug pusher to advance theplugs; a plug insertion tool having a support block for engaging andremoving a plug from the plug strip-off end of each magazine and forinserting the plug into a service entrance of the conduit; and a remoteoperated injection device for delivering a sealing material into theplug inserted into the service entrance, the injection device includinga nozzle located within the support block of the plug insertion tool, aremote controlled dispensing valve connected to the nozzle, and acartridge of sealing material connected to the dispensing valve.
 2. Theapparatus of claim 1, wherein the injection device further comprises astatic mixer connected to the nozzle.
 3. The apparatus of claim 1,wherein the injection device is pneumatically operated.
 4. The apparatusof claim 2, wherein the sealing material is a multi-part sealingmaterial.
 5. The apparatus of claim 1, comprising two or more plugdispensing magazines mounted onto the remotely controlled robot.
 6. Theapparatus of claim 5, wherein each of the two or more plug dispensingmagazines are pre-loaded with the same sized plug to allow for a greatercapacity of plugs for conduits having a very large number of serviceentrances of the same size within the conduit.
 7. The apparatus of claim5, wherein each of the two or more plug dispensing magazines arepre-loaded with different sized plugs to accommodate different sizedservice entrances within the conduit.
 8. The apparatus of claim 1,wherein the biasing member of each magazine is a spring applying aconstant force to the pusher to advance the plugs down the magazine asthey are being released.
 9. The apparatus of claim 1, wherein the atleast one spring loaded retaining finger at the plug strip-off end ofeach magazine has a retaining force greater than the plug advancingforce of the biasing member to keep the plugs from being pushed through.10. The apparatus of claim 1, wherein the at least one spring loadedretaining finger includes two retaining fingers.
 11. The apparatus ofclaim 1, wherein the at least one spring loaded retaining finger is madeof flexible spring steel.